org.apache.http.nio.entity
Class NFileEntity

java.lang.Object
  extended by org.apache.http.entity.AbstractHttpEntity
      extended by org.apache.http.nio.entity.NFileEntity
All Implemented Interfaces:
HttpEntity, ProducingNHttpEntity

public class NFileEntity
extends AbstractHttpEntity
implements ProducingNHttpEntity

A self contained, repeatable non-blocking entity that retrieves its content from a file. This class is mostly used to stream large files of different types, so one needs to supply the content type of the file to make sure the content can be correctly recognized and processed by the recipient.

Since:
4.0
Version:
$Revision: 744542 $

Field Summary
 
Fields inherited from class org.apache.http.entity.AbstractHttpEntity
chunked, contentEncoding, contentType
 
Constructor Summary
NFileEntity(File file, String contentType)
           
NFileEntity(File file, String contentType, boolean useFileChannels)
          Creates new instance of NFileEntity from the given source File with the given content type.
 
Method Summary
 void finish()
          Notification that any resources allocated for writing can be released.
 InputStream getContent()
          Creates a new InputStream object of the entity.
 long getContentLength()
          Tells the length of the content, if known.
 boolean isRepeatable()
          Tells if the entity is capable of producing its data more than once.
 boolean isStreaming()
          Tells whether this entity depends on an underlying stream.
 void produceContent(ContentEncoder encoder, IOControl ioctrl)
          Notification that content should be written to the encoder.
 void writeTo(OutputStream outstream)
          Writes the entity content to the output stream.
 
Methods inherited from class org.apache.http.entity.AbstractHttpEntity
consumeContent, getContentEncoding, getContentType, isChunked, setChunked, setContentEncoding, setContentEncoding, setContentType, setContentType
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.http.HttpEntity
consumeContent, getContentEncoding, getContentType, isChunked
 

Constructor Detail

NFileEntity

public NFileEntity(File file,
                   String contentType,
                   boolean useFileChannels)
Creates new instance of NFileEntity from the given source File with the given content type. If useFileChannels is set to true, the entity will try to use FileContentEncoder interface to stream file content directly from the file channel.

Parameters:
file - the source file.
contentType - the content type of the file.
useFileChannels - flag whether the direct transfer from the file channel should be attempted.

NFileEntity

public NFileEntity(File file,
                   String contentType)
Method Detail

finish

public void finish()
Description copied from interface: ProducingNHttpEntity
Notification that any resources allocated for writing can be released.

Specified by:
finish in interface ProducingNHttpEntity

getContentLength

public long getContentLength()
Description copied from interface: HttpEntity
Tells the length of the content, if known.

Specified by:
getContentLength in interface HttpEntity
Returns:
the number of bytes of the content, or a negative number if unknown. If the content length is known but exceeds Long.MAX_VALUE, a negative number is returned.

isRepeatable

public boolean isRepeatable()
Description copied from interface: HttpEntity
Tells if the entity is capable of producing its data more than once. A repeatable entity's getContent() and writeTo(OutputStream) methods can be called more than once whereas a non-repeatable entity's can not.

Specified by:
isRepeatable in interface HttpEntity
Returns:
true if the entity is repeatable, false otherwise.

produceContent

public void produceContent(ContentEncoder encoder,
                           IOControl ioctrl)
                    throws IOException
Description copied from interface: ProducingNHttpEntity
Notification that content should be written to the encoder. IOControl instance passed as a parameter to the method can be used to suspend output events if the entity is temporarily unable to produce more content.

When all content is finished, this MUST call ContentEncoder.complete(). Failure to do so could result in the entity never being written.

Specified by:
produceContent in interface ProducingNHttpEntity
Parameters:
encoder - content encoder.
ioctrl - I/O control of the underlying connection.
Throws:
IOException

isStreaming

public boolean isStreaming()
Description copied from interface: HttpEntity
Tells whether this entity depends on an underlying stream. Streamed entities should return true until the content has been consumed, false afterwards. Self-contained entities should return false. Wrapping entities should delegate this call to the wrapped entity.
The content of a streamed entity is consumed when the stream returned by getContent has been read to EOF, or after consumeContent has been called. If a streamed entity can not detect whether the stream has been read to EOF, it should return true until consumeContent is called.

Specified by:
isStreaming in interface HttpEntity
Returns:
true if the entity content is streamed and not yet consumed, false otherwise

getContent

public InputStream getContent()
                       throws IOException
Description copied from interface: HttpEntity
Creates a new InputStream object of the entity. It is a programming error to return the same InputStream object more than once. Entities that are not repeatable will throw an exception if this method is called multiple times.

Specified by:
getContent in interface HttpEntity
Returns:
a new input stream that returns the entity data.
Throws:
IOException - if the stream could not be created

writeTo

public void writeTo(OutputStream outstream)
             throws IOException
Description copied from interface: HttpEntity
Writes the entity content to the output stream.

Specified by:
writeTo in interface HttpEntity
Parameters:
outstream - the output stream to write entity content to
Throws:
IOException - if an I/O error occurs


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